This invention refers to a self-closing cap for the filler necks of liquid containers such as barrels, canisters, tanks and the like, as well as fuel tanks of motor vehicles, comprising a closure ring with a seal, said ring being attachable to the filler neck and having an orifice for receiving a nozzle that discharges a pressurized stream of liquid into the container, and a closure flap swivel-mounted on said closure ring and provided with a seal, said flap being opened during the filling of the container by the insertion of the nozzle into the filler neck and automatically closing under the influence of a spring upon withdrawal of the nozzle from the filler neck, wherein the improvement is the provision of a gasket around the orifice for preventing atomized liquid from being discharged out of the orifice and onto the hand of the person operating the nozzle.
A wide variety of filler neck caps for the fuel tanks of automotive vehicles are known in the prior art. In many of these filler neck caps, the applicants have noticed that the pivoting closure flap can obstruct the amount of space between the nozzle of the gas pump and the orifice in the center of the cap to an extent to where atomized fuel can be blown back out of the tank and onto the hand of the person handling the pump nozzle as the pressurized stream of liquid and volatile fuel displaces air from the tank during the tank filling operation. This is a significant shortcoming, since the volatile components of fuel can soak into the skin which is not only unhealthy, but causes the hand of the nozzle operator to smell of gasoline or the like. Still another shortcoming of such prior art filler caps results from the fact that the filler necks of some automobiles include a built-in "trap door" structure a few inches down from their upper ends through which the end of the fuel pump nozzle must be inserted before fuel can enter the tank. If a filler cap of the type previously described is mounted onto such a filler neck, it becomes difficult to insert the nozzle through both the closure flap of the cap and the trap door of the filler neck since the cap orifice is necessarily smaller than the opening on top of the filler neck.